Thiabendazole: adverse event reports that FDA received
Active ingredient
The Green Book lists no brand name for exactly this active ingredient.
The openFDA records give the value "MSK" for the brand name and for the manufacturer name of each drug. FDA says that MSK means "masked". So the site cannot count a report for a brand.
Read this first. FDA says this about the data:
An API dataset query result cannot be used to estimate the risk associated with the product or compare one drug or device product with another. When looking at the results, be aware that there is no certainty that the reported drug or device caused the adverse event. This dataset should not be the sole source of information for clinical decision-making or other assumptions about the safety or effectiveness of a product. The adverse event may have been related to an underlying disease, other drugs used at the same time or other non-drug related sources.
FDA Center for Veterinary Medicine publishes these words. Source: Adverse Event Reports for Animal Drugs and Devices, read on . The data have the reports that FDA received through .
This page is not veterinary advice. For an animal that is ill, speak to a veterinarian.
Contacting a veterinarianHow to report to FDAFrom November 1987 to August 2014, FDA received 56 adverse event reports that name a drug with thiabendazole as its active ingredient. Of the 56 reports, 21 (37.5%) are about dogs. 8 reports are about people who were exposed to the drug (14.3%).
In January to March 2026, FDA received no reports that name this drug. The sign that appears in the largest number of the 56 reports is "Uncoded sign". A report is not proof that a drug caused a sign.
Fewer than 20 reports named this drug in the 12 months before June 2026, so this page gives no change. Reports about dogs are 37.5% of the reports that name this drug, and 72.6% of all reports.
Search engines list a drug page with 500 reports or more in all years. The page also needs 30 reports or more in the 12 months to June 2026. This page is under one of these numbers. The site keeps the page and keeps it out of search engines.
Since the last update of the FDA data
The latest update of the FDA data, recorded on , changed no count of this page.
January to March 2026 is the latest closed quarter in the data. In that quarter FDA received 0 reports that name thiabendazole: 0 dog, 0 cat, 0 horse, 0 other or not given.
Signs that the reports list
A sign is a coded term from the report. The words in brackets are a plain gloss of the term. The percentage is the share of the 56 reports that list the sign. One report can list more than one sign.
The sign that is in the largest number of the reports comes first.
- Uncoded sign[a sign with no matching dictionary term]25%14 reports
- Death8.9%5 reports
- Dropper, Abnormal8.9%5 reports
- Eye irritation8.9%5 reports
- Caps, Abnormal[a product quality report, not a sign in an animal]7.1%4 reports
- Vials, Leaking[a product quality report, not a sign in an animal]7.1%4 reports
- Accidental exposure[exposure that was not intended]5.4%3 reports
- Deafness NOS[NOS: not otherwise specified]5.4%3 reports
- External ear disorder NOS[NOS: not otherwise specified]5.4%3 reports
- Eye redness5.4%3 reports
- Lethargy[unusually tired or inactive]5.4%3 reports
- Anorexia[not eating]3.6%2 reports
- Application site erythema[reddened skin where the product was applied]3.6%2 reports
- Ataxia[unsteady, uncoordinated movement]3.6%2 reports
Show the next 16 signs
- Behavioural disorder NOS[behaviour change, type not specified]3.6%2 reports
- Deafness3.6%2 reports
- Diarrhoea[diarrhea]3.6%2 reports
- Elevated alanine aminotransferase (ALT)[a liver enzyme above the normal range]3.6%2 reports
- Elevated liver enzymes[liver enzymes above the normal range]3.6%2 reports
- Facial swelling3.6%2 reports
- Pinnal reddening3.6%2 reports
- Tachycardia[fast heart rate]3.6%2 reports
- Vomiting3.6%2 reports
- Abnormal birth weight1.8%1 reports
- Aggression1.8%1 reports
- Anaemia NOS[low red blood cell count]1.8%1 reports
- Anaphylaxis[sudden severe allergic-type reaction]1.8%1 reports
- Application site blister[blister where the product was applied]1.8%1 reports
- Application site hair change[hair change where the product was applied]1.8%1 reports
- Application site irritation[irritation where the product was applied]1.8%1 reports
The list shows 30 of 74 coded signs. A report is not proof that a drug caused a sign. Download all signs (CSV)
Reports by species
The share is of all 56 reports that name thiabendazole. The other reports give a different species or no species.
Reports for each month, Jul 2021 to Jun 2026
No chart: no month has 5 or more reports.
No chart: no month has 5 or more reports.
No chart: no month has 5 or more reports.
No chart: no month has 5 or more reports.
The month is the month in which FDA received the report. Each chart has its own scale. FDA says that a report can take 3 to 6 months to reach the public data. The newest months can get more reports in a later update.
Reports by year
- Dog
- Cat
- Horse
- Other or not given
| Year | Dog | Cat | Horse | Other or not given | All species |
|---|---|---|---|---|---|
| 2014 | 1 | 0 | 0 | 0 | 1 |
| 2012 | 6 | 3 | 0 | 1 | 10 |
| 2011 | 14 | 4 | 0 | 13 | 31 |
| 2010 | 0 | 0 | 0 | 8 | 8 |
| 1999 | 0 | 0 | 0 | 1 | 1 |
| 1996 | 0 | 0 | 0 | 1 | 1 |
| 1991 | 0 | 0 | 0 | 1 | 1 |
| 1990 | 0 | 0 | 0 | 1 | 1 |
| 1989 | 0 | 0 | 0 | 1 | 1 |
| 1987 | 0 | 0 | 0 | 1 | 1 |
2014 has the reports that FDA received through Aug 2014. Download the years (CSV)
What the reports record
Outcome at the time of the report
- Recovered/Normal16.1%9
- Recovered with Sequela[recovered, with a lasting effect]1.8%1
- Ongoing0%0
- Died7.1%4
- Euthanized0%0
- Outcome Unknown46.4%26
An outcome in a report is not proof that the drug caused it. The person who sends the report gives the outcome. Each share is of the 56 reports that name thiabendazole.
A report about more than one animal can have more than one outcome.
Kind of report
- Safety issue73.2%41
- Lack of expected effectiveness0%0
- Both safety and lack of expected effectiveness0%0
- Manufacturing or product defect26.8%15
- Other0%0
36 reports say if the event was serious. 50% of them have the serious flag. The person who sends the report sets the flag.
Show age, weight, breed and route
Age of the animal
- Under 1 year7.1%4
- 1 to 3 years10.7%6
- 4 to 7 years17.9%10
- 8 to 11 years7.1%4
- 12 years and over12.5%7
- Age not given44.6%25
Weight of the animal
- Under 5 kg (11 lb)12.5%7
- 5 to 9.9 kg (11 to 22 lb)12.5%7
- 10 to 24.9 kg (22 to 55 lb)10.7%6
- 25 to 44.9 kg (55 to 99 lb)8.9%5
- 45 kg and over (99 lb and over)8.9%5
- Weight not given46.4%26
Breed, where the report gives one breed
- Domestic Shorthair10.7%6
- Brahman1.8%1
- Akita1.8%1
- Bulldog1.8%1
- French Bulldog1.8%1
- Great Dane1.8%1
- Japanese Chin (Spaniel)1.8%1
- Maltese1.8%1
A breed with many animals has many reports.
Route in the report
- Auricular (Otic)33.9%19
- Ophthalmic17.9%10
- Oral12.5%7
Each bar is on a scale of 0 to 100%.
Approved animal drugs with this active ingredient (FDA Green Book)
This section is reference data. It has no report count.
The openFDA records give the value "MSK" for the brand name and for the manufacturer name of each drug. FDA says that MSK means "masked". So the site cannot count a report for a brand.
| Brand name | Active ingredients | Sponsor | Approved species | Application |
|---|---|---|---|---|
| Thibenzole Sheep & Goat Wormerapproval withdrawn | Thiabendazole | Boehringer Ingelheim Animal Health USA Inc. | Sheep, Goats | NADA 013-022 |
| Equizole Horse Wormerapproval withdrawn | Thiabendazole | Boehringer Ingelheim Animal Health USA Inc. | Horses | NADA 013-407 |
| Thibenzole 20% Swine Premixapproval withdrawn | Thiabendazole | Boehringer Ingelheim Animal Health USA Inc. | Swine | NADA 013-954 |
| Omnizoleapproval withdrawn | Thiabendazole | Boehringer Ingelheim Animal Health USA Inc. | Cattle, Sheep, Goats | NADA 014-350 |
| TBZ Cattle Wormer (Drench)approval withdrawn | Thiabendazole | Boehringer Ingelheim Animal Health USA Inc. | Cattle | NADA 015-123 |
| TBZ 200 Medicated Feed Premixapproval withdrawn | Thiabendazole | Boehringer Ingelheim Animal Health USA Inc. | Cattle, Swine, Sheep, Goats | NADA 015-875 |
| Thibenzole (18 mg)approval withdrawn | Thiabendazole | Boehringer Ingelheim Animal Health USA Inc. | Cattle | NADA 030-103 |
| E-Z-EX Wormer Pelletsapproval withdrawn | Thiabendazole | ADM Animal Nutrition | Cattle, Sheep, Goats | NADA 030-578 |
| Equizoleapproval withdrawn | Thiabendazole | Boehringer Ingelheim Animal Health USA Inc. | Horses, Cattle, Sheep, Goats | NADA 034-114 |
| Thibenzole Pig Wormerapproval withdrawn | Thiabendazole | Boehringer Ingelheim Animal Health USA Inc. | Swine | NADA 035-631 |
| Purina Horse Wormer Medicatedapproval withdrawn | Thiabendazole | Virbac AH, Inc. | Horses | NADA 040-205 |
| E-Z-EX Wormer Mintrate Blockapproval withdrawn | Thiabendazole | ADM Animal Nutrition | Cattle | NADA 042-910 |
| Thibenzole 300 Medicatedapproval withdrawn | Thiabendazole | Boehringer Ingelheim Animal Health USA Inc. | Cattle | NADA 043-141 |
| Equizole Horse Wormer Pelletsapproval withdrawn | Thiabendazole | Boehringer Ingelheim Animal Health USA Inc. | Horses | NADA 044-654 |
| TBZ Wormer Paste 50%approval withdrawn | Thiabendazole | Boehringer Ingelheim Animal Health USA Inc. | Cattle | NADA 048-487 |
| TBZ Wormer Paste 43%approval withdrawn | Thiabendazole | Boehringer Ingelheim Animal Health USA Inc. | Cattle | NADA 049-461 |
| Equizole 50% Wormer Paste; Equizole 50% Wormer Paste For Horsesapproval withdrawn | Thiabendazole | Boehringer Ingelheim Animal Health USA Inc. | Horses | NADA 098-689 |
Other pages with this ingredient
A report names a drug by its set of active ingredients. Each set has its own page. The list is in order of name.
Next in the A to Z list
FDA pages for this drug
- How to Report Animal Drug and Device Side Effects and Product ProblemsThe FDA page that tells an owner or a veterinarian how to send a report.
- Animal Drugs @ FDAThe search page of the Green Book, the FDA list of approved animal drugs.
The site checked these addresses on . The links open in a new tab.
Cite this page
Pet Drug Reports. Thiabendazole: adverse event reports that FDA received. https://petdrugreports.com/drug/thiabendazole/ Source: FDA Center for Veterinary Medicine, openFDA Animal and Veterinary adverse event reports, export of . Reports received through .
Where the data come from
The counts come from the openFDA Animal and Veterinary adverse event files, export of 30 Oct 2026. The files have the reports that the FDA Center for Veterinary Medicine received through 26 Jun 2026. The files mask brand and manufacturer names. The site counts a drug by the active ingredients that each record gives, and gives no count to a brand, an application or a company. Ingredient names and the lists of approved products follow the FDA Green Book of 2 Nov 2026. The site does not use the application number that a record has.
The site does not publish report text, lot numbers or details of a reporter. FDA's record is the authority. See how the site counts reports, the data sources and the corrections page.
Questions about these reports
- Which brand are these reports about?
The openFDA records give the value "MSK" for the brand name and for the manufacturer name of each drug. FDA says that MSK means "masked". So the site cannot count a report for a brand. The Green Book lists no brand name for exactly this active ingredient.
- Do the reports show that the drug caused the signs?
No. FDA states this about the data.
When looking at the results, be aware that there is no certainty that the reported drug or device caused the adverse event.
The adverse event may have been related to an underlying disease, other drugs used at the same time or other non-drug related sources.
FDA Center for Veterinary Medicine. Source: Adverse Event Reports for Animal Drugs and Devices
- How many reports did FDA receive in the latest 12 months?
FDA received no reports in the 12 months to June 2026. It received no reports in the 12 months before. FDA says that a report can take 3 to 6 months to reach the public data. The newest months can get more reports in a later update.
- What kinds of report are in the count?
Of the 56 reports received from November 1987 to August 2014, 73.2% are about a safety issue only. 26.8% are about a defect of the product or its package.